Various types of memory devices store data in NAND Flash memory cells that are arranged in a three-dimensional (3D) structure. These technologies are commonly known as “3D NAND.” In one example configuration, the memory cells in a given plane of the 3D memory are arranged in strings. The memory cells in each string are connected to one another in a source-to-drain cascade. A source-selection transistor (referred to as SGS) and a drain-selection transistor (referred to as SGD) are connected at the source and drain ends of the string, respectively, and enable selection of the string for programming, readout or erasure.